In the first volume will be found an account of the _Lemuroidea_, and the
_Anthropoidea_ as far as the group of the Macaques of the family
_Cercopithecidæ_. The second volume continues with the latter genus, and
contains the rest of the Monkeys, and the Apes, as well as a summary of the
geographical distribution of the species of the Order Primates.
I have not attempted to write a complete synonymy of the species of
Monkeys. The literature is scattered over many, often obscure, periodicals,
and without seeing the actual specimens described by some of the older
writers, it would be easy to introduce a great deal of confusion into the
synonymy. I have, therefore, only attempted to give the principal
references.
I must express my obligation to Dr. Günther, F.R.S., the Keeper of the
Zoological Department in the British Museum, for the facilities of study
afforded to me in that institution. To Mr. Oldfield Thomas I am likewise
greatly indebted for much assistance, and for many a kindly hint.
Dr. Forsyth Major, who is well-known as one of the foremost authorities on
the Lemurs, not only gave me valuable information as to the species and
literature of the _Lemuroidea_, but was even so good as to furnish me with
the descriptions of several new species.
Lastly, to my friend the Editor, I have to return my sincere thanks for the
patience with which he has revised my MSS., and for the verification of
numbers of references, only to be found in the great libraries of London,
and inaccessible to an author dwelling in the provinces.